<!doctype html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport"
          content="width=device-width, user-scalable=no, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>
<div>
    <form>
        <h3>用户登录</h3>
        <div>
            <label>用户名：</label>
            <br/>
            <input type="text" name="user" placeholder="请输入用户名">
            <span>[6-10]</span>
        </div>
        <div>
            <label>密码：</label>
            <br/>
            <input type="password" name="password" placeholder="请输入密码">
            <span>六位数字</span>
        </div>
    </form>
</div>
</body>
</html>